Acoustic evaluation of penetrations in drywall constructions

In the design of drywall constructions for office buildings with airborne sound insulation requirements, penetrations, such as cables, cable bundles, or ventilation ducts, are typically not included in acoustic calculations. For this reason, a research project was conducted to examine the impact of various types of penetrations on the weighted sound reduction index (Rw) of different drywall partitions. Laboratory measurements were performed on four drywall constructions, testing over 180 modifications. Starting with properly installed, penetration-free walls, different penetrations were introduced, and their effects on Rw were measured. The results demonstrated significant reductions in sound insulation, depending on the penetration type and installation quality. Key factors included the precision of the opening and the size of the unfilled residual cross-sectional area. The ongoing analysis aims to determine whether the initial wall sound insulation correlates with penetration effects, such as greater sound insulation amplifying the impact of penetration on its reduction. Based on these findings, it is recommended to incorporate an additional safety margin in the design phase, tailored to the specific type of penetration, to better address its potential impact on sound insulation.